Senator Matthew H. Cochrane had been one of the foremost advocates for the new lease regulations put in place by Prime Minister John A. MacDonald. A successful man of business with influential connections in Ottawa, he was given his choice of 100,000 acre leases, and was ranching in the Big Hill area even before the new legislation was passed.
Cochrane purchased his first herd of 6,700 cattle in Montana, but the long drive up to the Cochrane range site, and the subsequent harsh winter, left the herd significantly diminished. In addition, the hair brands - made by scraping off a pattern of hair from the animal with a knife - had disappeared by the spring of 1882, and the ranch manager, Col. James Walker, decided that all the cattle in the vicinity should be rounded up and properly identified - with his own brand. Neighbouring ranchers understandably disagreed with the process, and retaliated by branding many Cochrane cattle as their own. Another considerable loss of animals was endured the following year, when a purchase of 5,000 cattle was driven northward, under Cochrane's orders, through heavy snows. Walker, frustrated with the company's directors, resigned in 1882, and his place was taken by Frank White, treasurer and general manager, and William Kerfoot as range manager.
By 1886, William F. Cochrane, one of the senator's sons, had succeeded White as manager of a more southerly-located Cochrane Ranch. Despite his capable leadership, the severe winter of 1886-87 caused heavy losses of stock. The possibility of like disasters convinced many ranchers that they must put up hay for winter feed.
Despite setbacks, the Cochrane Ranch prospered, and a new acreage was purchased in 1896. When Senator Cochrane died in 1903, however, so did its driving force, and the ranch was sold in 1905. It had been the first great ranch, and the largest of its time.